Earth’s curvature is hard to observe from the surface. Even from the altitude of a commercial passenger flight, about 30000-40000 ft, Earth’s curvature is still too small to notice. However, under careful observation, it is not impossible to confirm the curve from the cruising altitude of a jet airliner.
A large amount of flat Earth memes present an image taken from a high-altitude balloon, showing the appearance of a flat horizon. Such images evidently cannot be regarded as “proof” of a flat Earth. The horizon appears flat only because of the barrel distortion from the fisheye lens.
The following is how any unscrupulous flat-Earther try to deceive us using footages from high-altitude balloons.
A ring laser gyroscope (RLG) is an instrument for measuring the change in orientation and rotational velocity. It is sensitive enough to measure Earth’s rotation easily.
Flat-Earthers claim that there is no instrument able to measure Earth’s rotation. Such claim arose from their ignorance. Ring laser gyroscopes —which are installed in some airplanes and ships— can easily detect and measure Earth’s rotation.
If the Earth were flat, then the Sun has to be visible above the horizon all the time, from the entire Earth. This does not occur, and the simple fact should have been sufficient to rule out any possibility of a flat-Earth.
But instead, flat-Earthers invented various convoluted chain of ad-hoc hypotheses and presented them as “explanations” to prevent the flat-Earth model from being falsified. None of the “explanations” are proven nor correspond to the way our world works.
The apparent size of the Moon remains constant in a single day. This can only happen if the Moon is practically at the same distance all day.
In the flat-Earth model, the Moon is thought to be moving in a circle above the flat Earth. Such a notion should cause the Moon apparent size to vary in a day. However, in reality, the Moon appears in the same size all day, and it proves that the flat-Earth model does not represent reality and that the Moon is much farther.
The weight of an object is the force exerted on the object by gravity. The gravitational force exerted by the Earth on an object is what we refer to as ‘weight’.
Many flat-Earthers fail to understand that the gravitational force is just another name for ‘weight’. Many misconceptions in the communities of flat Earth victims arise from such a misunderstanding.
Smoke rises due to convection current. The solid particles emitted from a combustion process are carried by the hot air that rises because of its lower density than the surrounding air. The horizontal motion of smoke itself is affected by the movement of air surrounding it.
Flat-Earthers claim that a rising smoke without horizontal motion “proves” a stationary Earth. They are wrong. The horizontal motion of smoke is an effect of the horizontal motion of air relative to the smoke, and the motion of the object emitting the smoke is inconsequential.
There are many space agencies from multiple countries. Some are from countries that are rivals or even enemies at some point in history. Even so, practically all their findings corroborate each other. Any made up claims or fabrications would have been noticeable and found very quickly.
Flat-Earthers accuse NASA of being part of the so-called globe Earth conspiracy, with the purpose of spreading “globe Earth propaganda” to the world population. However, there other space agencies, which are independent and employ thousands of staffs. And every one of them practically confirms NASA’s findings.
In most situations, atmospheric refraction bends light downwards and causes objects to appear higher than they actually are. The strength of atmospheric refraction is not constant. It depends on weather condition and varies on the different seasons, different days, and even different times of the day.
Because of the variability of atmospheric refraction, a distant object that is usually obstructed by Earth’s curvature can sometimes be visible. Some flat-Earthers would cherry-pick moments when the object is visible. They would show such specific moments to everyone and use them to “disprove” Earth’s curvature; happily ignoring the cases where Earth’s curvature partly or entirely obstructs the object.
Fiber-optic communication is a method of transmitting data by sending pulses of light through an optical fiber. These days, the majority of data communication involves a fiber-optic connection. However, other methods of transmitting data exist, including satellites.
Flat-Earthers use the prominence of fiber-optic communication as “proof” of the nonexistence of satellites. Such a line of thinking is a fallacy of hasty generalization. Using the same “logic,” we can “prove” trains don’t exist just by showing the existence of cars.
A panorama image is stitched from multiple photos that were taken from different angles, forming a very wide field of view, even 360°×180°, covering every possible angle from the viewer.
Someone has taken a panorama from a high-altitude balloon and made available the results in various projections. Flat-Earthers saw a flat horizon in one of the panorama images and took the wrong conclusion. The horizon will appear flat in a cylindrical or equirectangular projection due to an effect of the projection. The panorama creator also has the panorama in other formats, including an interactive one in the general perspective projection, which shows how it would look from a human eye, and it shows the curvature.
In 2017, the group who name themselves ‘ASAN’ staged a protest to Donald Trump by sending a high-altitude balloon carrying a camera and a crude message, which was quoted from a statement by Edgar Mitchell, an astronaut from the Apollo 14 mission.
Some unscrupulous flat-Earthers hijacked the protest and turned it as if ASAN did it to prove Earth’s curvature and to insult them. These flat-Earthers pointed out that ASAN somehow “forgot” to conceal the fact that a fisheye lens was used. In reality, it is never the intention of ASAN to prove Earth’s curvature, nor to throw insults to flat-Earthers.
China’s Chang’e 4 spacecraft has successfully landed on the Moon. It is the first ever spacecraft to land on the far side of the Moon.
Unfortunately, some news outlets used the term “dark side of the Moon” which is inaccurate. The side of the Moon where Chang’e 4 landed is not always dark, but instead always facing away from the Earth. That part of the Moon has the same day and night cycle like the side that is facing us and is not always dark.
Flat-Earthers were confused that the spacecraft use solar panels. If the side of the Moon is always dark, then it should be pointless to use solar panels. They took these facts as “proof” of some sort of misconduct. They were simply confused about the term some news outlets were using. The correct term is “far side of the Moon.”
A frame of reference consists of an abstract coordinate system and the set of physical reference points that uniquely fix the coordinate system and standardize measurements. Speed or velocity is relative to a frame of reference. It is possible that two speeds/velocities are measured relative to a different frame of reference and thus cannot be directly compared.
Flat-Earthers would often compare two different speed measurements like an airplane moving at 900 km/h (560 mph) and Earth’s surface near the equator at 1674 km/h (1040 mph). They would conclude the airplane should not be able to catch up with Earth’s surface and would not be able to land if the Earth is rotating. They are wrong. The speeds are measured relative to the different frame of reference, and therefore, cannot be compared directly.
Troposcatter is a signal propagation method using the scattering phenomenon in the upper troposphere. As the signal pass through the upper troposphere, some of the energy is scattered back toward Earth, allowing the receiver station at the correct location to pick up the signal.
White Alice is a decommissioned troposcatter network in North America. Some flat-Earthers invented the “explanation” that the various satellite-based services we enjoy today are using White Alice. They are wrong. White Alice and other troposcatter networks cannot possibly replace all the services provided by satellites.
Due to Earth’s axial precession, the positions of Earth’s celestial poles shift gradually in a cycle of approximately 26000 years. These days, Polaris is very close to the north celestial pole. However, 2000 years ago, Kochab is much closer to the celestial pole than Polaris. In the next 2000 years, Errai will replace Polaris as our pole star.
Flat-Earthers claim that the stars are always in the same position proves the Earth is stationary. They are wrong. By observing old star charts from a few centuries ago, the shift of celestial poles can be determined. It proves stars are not always in the same position as today, and that the Earth is rotating.
The Tycho Crater is a crater on the Moon having the diameter of 85 km (53 miles). It is too small to recognize using the naked eye. However, it lies on a bright colored highland that can be mistaken as the crater itself. The crater also has an extensive ray system, which was from the ejected materials when the crater was formed.
Flat-Earthers claimed the visibility of the Tycho Crater proves the Moon is not that far. They are wrong. We cannot see the Tycho Crater using the naked eye. What is visible is the highland it lies on or its extensive ray system.
NASA has published several pictures of the Earth that are composites. It means the pictures were the result of combining many images into a single picture. In most cases, the source pictures were taken from low-orbiting satellites to obtain higher resolution pictures of the Earth.
Flat-Earthers discovered the photos are composites and claimed to have exposed “yet another evidence” of wrongdoing. They would publish this “findings” everywhere to turn us emotional. They are wrong. Nobody is covering the fact the pictures are composites, and there is no intention to deceive. Information that the photos are composites can be readily found in NASA’s website, far before the claimed “discovery” by flat-Earthers.
- Claimed by: FE Photographer
- Object 1:
- Name: Clark Island
- Distance: 19.59 mi (31.53 km)
- Elevation: 95 ft (29 m)
- Object 2:
- Name: Green Channel Marker Buoy
- Distance: 6.45 mi (10.38 km)
- Object 3:
- Name: Red Channel Marker Buoy
- Distance: 8.16 mi (13.13 km)
- Location: Bayview State Park
- Elevation: 17 ft (5.18 m)
Sailors sometimes need to estimate the range of a distant contact. Without radars, the only readily available reference point for estimating ranges is the horizon.
By knowing the height of the observer from the waterline, it is possible to calculate the distance to the horizon, and thus, it is possible to determine the distance to a remote contact, relative to the horizon. It is possible to do this only because the Earth is spherical.